Truck cab suspension



April 17, 1951 c. F. KRAMER 2,549,102

TRUCK CAB SUSPENSION Filed Feb. 14, 1946 3 Sheets-Sheet 1 @u E CLARE/vc:KBA/mma HVVENTR.

A T'URNEYS.

Patented Apr. 17, 1951 TRUCK CAB SUSPENSION Clarence F. Kramer,Birmingham, Mich., assignor to Ford Motor Company, Dearborn, Mich., a

corporation of Delaware Application February 14, 1946, Serial No.647,577

3 Claims. (Cl. 296-35) This invention is concerned with a method andmeans for suspending a truck cab from a truck frame.

An object of this invention is to provide a new and improved method andapparatus'for fastening a truck cab to the truck frame. This inventionis designed to eliminate the transmission of strain from the truck frameto the cab and has particular reference to the strain resulting fromtwisting of the frame.

The invention is illustrated in the drawings in which:

Figure 1 is a perspective view partially in section of a single truckcab suspension means.

Figure 2 is a perspective view of a truck cab.

Figure 3 is an elevation partially in section of a pair of truck cabsuspension means.

Figure 4 is a view partially in section of an alternate cab suspensionmeans.

Figure 5 is a cross section of the cab suspension arm.

Figure 6 is a section of the structure shown in Figure 4 along the line6 6.

' Figure '7 is a section showing a detail of the bearing used in thestructures depicted in Figures l and 3.

Truck cab bodies have heretofore been mounted upon truck frames by meansof bolts, but with a spring interposed between the cab and frame.Conventionally this spring has taken the usual helical form with themounting bolt arranged axially within the helix. This yielding type ofmounting has been necessitated by the substan tial amount of twist whichoccurs in the long frames of present day trucks due to uneven loadingand road irregularities. If the cab were rigidly secured to the frame atall four corners, any twisting in the frame would necessarily becommunicated directly to the body and engender noise and binding in thedoors and windows. The use of the spring mounting mentioned abovesatisfactorily eliminated twist in the cab, but introduced a new sourceof trouble due to noise and wear occasioned by the reciprocation of thebolt in the bolt hole.

The present invention retains the advantages of former yieldingmountings and eliminates the noise and wear associated therewith. Theinvention is probably best understood by reference to the drawings whichdepict the mountings for the rear edge of a truck cab.

Figure 3 is an elevation of the truck cab suspension assembly as appliedto the rear edge of the cab. In this drawing for the sake of clarity themid-section of the assembly has been broken Y sideration of Figure 3.

away. The necessary resiliency is obtained from a pad I0 which iscomposed of rubber or a similar elastomer. This pad is in the form of ablunt wedge (Figure 1) and is provided with recesses I5 to accommodatethe bolt heads which secure the frame bracket 22 to frame I8. This padI0 is confined between and coacts with frame bracket 22 and suspensionarm I6. l Frame bracket 22 may be a steel stamping and is provided withupturned side ears 24 and similarly upturned end ear 23. These earssupport pad IB against lateral displacement and bulging as will be morefully explained hereinafter. This bracket is bolted to frame I8 which islocally strengthened by reinforcement I9. Frame bracket 22 hasintegrally formed bosses which given an adequate bearing surface tosupport bolt 2l and bushing 30 upon which revolves suspension arm. I6.This particular bearing structure is shown in Figure 7 which ispartially in section. Frame bracket 22 is shown provided with bosses 28ared. outwardly and suspension arm I6 with bosses 29 which are aredinwardly. These bosses are sized to accommodate bushing 3D which is heldin place by bolt 2 I.

The upper end of suspension arm I6 is mounted in body bracket I4 whichis securely welded to cab skirt 25 and turned down portions of cab sillI2 and cab floor II. Body bracket I4 is also provided with integralbosses which provide a bearing surface for bolt 21 and an associatedbushing in which revolves suspension arm I6. This bearing is similar tothat shown in Figure 7.

In employing this type of mounting, the front edge of the cab is rigidlysecured to the frame and the suspension described above employed on bothsides at the rear of the cab. The operation of this mounting is thoughtto be clear from a con- Assuming road or load conditions which wouldcause the portion of the frame supporting the rear of the cab to rotateclockwise as indicated by the heavy arrows in Figure 3, the pad IIJ inthe right hand suspension would be compressed by a resultant, relativecounterclockwise rotation of suspension arm I6. Such rotation ofsuspension arm I6 would of course compress pad I0 between suspension armI6 and frame bracket 22. The end ear 23 and side ears 24 prevent lateraldisplacement or flow of the rubber in pad I0 during such compression. Ofcourse, when load or road conditions change so as to reverse thedirection of twist, the pad I0 in the left hand suspension would becompressed.

The compression of these pads I0 provide sufcient resiliency to avoidundesired twisting of y 3 the cab. To demonstrate the eicacy of thistype of cab suspension, a truck so equipped was loaded to capacity. Ajack was then placed under the left front wheel and this wheel raiseduntil the right wheel was clear of the ground. Even with 5 the frametwisted to this extent, there was no Under certain circumstances ithasbeen found z.' advisable to substitute a forging or casting for-Vstamped suspension arm I6; Figures 4, 5 and 6 are directed to asuspension arm which is either a forging or casting. Figure 5 is asection of this cast arm comprising a web 32, a flange 33 u and. a bead34. The use of a. cast or forged arm makes possible a somewhat moreadvantageous bearing structure than is possible .with a stamped arm.`This bearing structure is generally similarto that used with the stampedarm, employ- 25 a substantial angleY to both' horizontal and ver- :z5

tical axes of the vehicle, one of the pivots upon which a suspension armturns comprising a` pin mounted in a receptacle containing a wedgeshaped` block of elastomer and having supporting members for lateralsupport ofthe elastomer, 40

the small angle of the-Wedge-shaped blockA of the elastomerapproximating they angle., included between the frame member andthe-suspension arm in thenormal position, said suspension arm, pivot andelastomer being arranged so that rotation is of the suspension armtowardy the `elastomer vcauses compression of the elastomer.l

Y 2. An automotive lvehicle comprising a body and av frame,` saidbodyybeing rigidly mounted onthe frame at two locations and beingresili- :v ently attachedV to the frame atj two other locations throughtwo suspension means each of This 1 0 which suspension means comprises arigid suspension arm connecting the vehicle body and frame, saidsuspension arm being pivotally connected to the body and frame andinclined at a substantial angle to both horizontal and vertical axes ofthe vehicle, one of the pivots upon which the suspension arms turnscomprising a pin mounted'in a receptacle containing a wedge shaped'block of elastomerA and having support ing members for lateral supportof the elastomer, the small angle of the wedge shaped block of the`elastomer'approximating the angle included between the frame member andthe suspension arm in the -normal position, said suspension arm, pivotand elastomer being arranged so that rotation oft the Vsuspension armtoward the elastomer causes compression of the elastomer.

3. A vehicle body suspension comprising a rigid Y, suspension armconnecting the Vehicle body and frame, said suspension arm beingpivotally connected to the body and frame and inclined at a substantialangle to both. horizontal and Vertical axes of the vehicle, one of thepivotsupon which a suspension arm turnsacomprising a pin supported bytheframe adjacentsJ receptacle containing a wedge shaped block of elastomerand `having supporting members for lateralsupport of. the elastomer, thesmall angle of the wedge shapedblock of elastomer approximating theangle included between the frame member and the suspension arm in thenormal p.ostion,.said suspension arm, pivot and elastomer being arrangedso thatrotation of the suspension arm toward the4 elastomerv causescompression of the elastemer.

CLARENCE F. KRAMER.

REFERENCES VCTT-ED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

